A prominent conservative voice and former presidential candidate, Jon Huntsman, now backs marriage equality, he announced today in an editorial.

Headlined "Marriage Equality Is a Conservative Cause," the former Utah governor and failed Republican presidential candidate wrote in The American Conservative that "we need to take a hard look at what today’s conservatism stands for."

He called marriage equality "the right thing to do" and warned that Republicans will continue to lose national elections if the party doesn't evolve. "The American people will not hear us out if we stand against their friends, family, and individual liberty," he wrote.

"Marriage is not an issue that people rationalize through the abstract lens of the law; rather it is something understood emotionally through one’s own experience with family, neighbors, and friends," Huntsman wrote. "The party of Lincoln should stand with our best tradition of equality and support full civil marriage for all Americans."

Huntsman, a Mormon, was already known as one of the more moderate candidates on LGBT equality. He served as President Obama's ambassador to China, and that close tie helped keep his campaign for president from taking off. As Utah's governor, Hunstman supported civil unions and continued to back only that kind of recognition while a candidate for president.

"Civil unions, I believed, were a practical step that would bring all citizens more fully into the fabric of a state they already were—and always had been—a part of," he explained today. "That was four years ago. Today we have an opportunity to do more: conservatives should start to lead again and push their states to join the nine others that allow all their citizens to marry."